The aim of this research is to evaluate myocardial fatty acid oxidation in comparison with mitochondrial oxidation using positron emission tomography with 11C-palmitate and 11C-acetate, respectively, in patients with medium- and long chain acyl-CoA dehydrogenase (MCAD and LCAD) deficiency and compare results to those obtained in normal volunteers. The long term goal is to evaluate whether the myocardial manifestations of MCAD and LCAD deficiency can be evaluated with noninvasive interrogation of myocardial metabolism.